DSpace Comunidad: Documentos resultantes de la investigación universitariahttp://hdl.handle.net/10045/162
Documentos resultantes de la investigación universitariaTue, 20 Mar 2018 03:51:35 GMT2018-03-20T03:51:35ZDSpace Comunidad: Documentos resultantes de la investigación universitariahttp://rua.ua.es:80/dspace/retrieve/49797/RuaInvestigacion.gifhttp://hdl.handle.net/10045/162
Influence of Waste Glass Powder Addition on the Pore Structure and Service Properties of Cement Mortarshttp://hdl.handle.net/10045/74327
Título: Influence of Waste Glass Powder Addition on the Pore Structure and Service Properties of Cement Mortars
Autor/es: Ortega, José Marcos; Letelier, Viviana; Solas, Carlos; Miró, Marina; Moriconi, Giacomo; Climent, Miguel-Ángel; Sánchez, Isidro
Resumen: At present, reusing waste constitutes an important challenge in order to reach a more sustainable environment. The cement industry is an important pollutant industrial sector. Therefore, the reduction of its CO2 emissions is now a popular topic of study. One way to lessen those emissions is partially replacing clinker with other materials. In this regard, the reuse of waste glass powder as a clinker replacement could be possible. This is a non-biodegradable residue that permanently occupies a large amount of space in dumping sites. The aim of this work is to study the long-term effects (400 days) of the addition of waste glass powder on the microstructure and service properties of mortars that incorporate up to 20% of this addition as clinker replacement. The microstructure has been characterised using the non-destructive impedance spectroscopy technique and mercury intrusion porosimetry. Furthermore, differential thermal analysis was also performed. Compressive strength and both steady-state and non-steady-state chloride diffusion coefficients have also been determined. Considering the obtained results, mortars with 10% and 20% waste glass powder showed good service properties until 400 days, similar to or even better than those made with ordinary Portland cement without additions, with the added value of contributing to sustainability.Fri, 16 Mar 2018 00:00:00 GMThttp://hdl.handle.net/10045/743272018-03-16T00:00:00ZSoft retention in height fall safety deviceshttp://hdl.handle.net/10045/74306
Título: Soft retention in height fall safety devices
Autor/es: Irles Más, Ramón; Pomares Torres, Juan Carlos; Segovia-Eulogio, Enrique-Gonzalo; Ferrer, Belén; Carrión Jackson, Elena
Resumen: Height falls in construction work cause fatal or serious accidents every year. Safety devices used to avoid this are supposed to stop the falling worker by developing forces that are low enough to prevent serious injury being caused during the retention process. In this paper three safety systems are analysed: collective protection such as safety nets (V-type) or provisory edge protection (C-class guardrails) and personal fall arrest systems (with a harness). There are many biological and mechanical variables involved in the retention process. Maximum or minimum values are needed for kinetic energy to be absorbed; the forces against a retained worker or system deflection, respectively, are required by certain codes governing the safety systems. Other codes only establish limits for some of these variables. Code criteria about cited requirements are not homogeneous and sometimes they are even inadequate due to a lack of knowledge about the relationships and implications concerning the mechanical variables. The corresponding interaction is difficult to evaluate and requires expensive experimental studies to be carried out on instrumented real size samples. Nevertheless, in the last decade, research on safety systems has been done on refined finite element models that can perform dynamic simulations of the impact. This paper contains important conclusions drawn from the original contributions of authors that suggest making relevant improvements to some of the corresponding codes. Comparisons of cheaper numerical predictions and real size experiments have proved that finite element models can be reliably used to analyse and design these safety devices.Wed, 01 Jan 2014 00:00:00 GMThttp://hdl.handle.net/10045/743062014-01-01T00:00:00ZDescription of the female of Labena madoricola González-Moreno & Bordera, 2015 (Hymenoptera, Ichneumonidae, Labeninae), with new records of Labena species from Mexicohttp://hdl.handle.net/10045/74325
Título: Description of the female of Labena madoricola González-Moreno & Bordera, 2015 (Hymenoptera, Ichneumonidae, Labeninae), with new records of Labena species from Mexico
Autor/es: González Moreno, Alejandra; Bordera Sanjuán, Santiago
Resumen: The female of Labena madoricola González-Moreno & Bordera, 2015 is described and illustrated for the first time from material collected with Malaise traps in 2016 in the Biocultural Reserve Kaxil Kiuic, Yucatán, Mexico. Diagnostic characters to distinguish females of New World Labena are provided. New distribution records of Labena species in Yucatán Peninsula, are also reported.Tue, 24 Oct 2017 00:00:00 GMThttp://hdl.handle.net/10045/743252017-10-24T00:00:00ZOlfactory Response of the Predatory Bug Orius laevigatus (Hemiptera:Anthocoridae) to the Aggregation Pheromone of Its Prey, Frankliniella occidentalis (Thysanoptera: Thripidae)http://hdl.handle.net/10045/74305
Título: Olfactory Response of the Predatory Bug Orius laevigatus (Hemiptera:Anthocoridae) to the Aggregation Pheromone of Its Prey, Frankliniella occidentalis (Thysanoptera: Thripidae)
Autor/es: Vaello, Teresa; Casas Martínez, José Luis; Pineda Gómez, Ana María; Alfonso, Ignacio de; Marcos-García, M. Ángeles
Resumen: Herbivore natural enemies base their foraging decision on information cues from different trophic levels but mainly from plant odors. However, the second trophic level (i.e., the herbivorous prey) may also provide reliable infochemical cues for their natural enemies. We have evaluated the role of the aggregation pheromone from Frankliniella occidentalis (Pergande) as a potential kairomone for its natural enemy, the predatory bug Orius laevigatus (Fieber). For this purpose, we have analyzed the response of O. laevigatus to (R)-lavandulyl acetate and neryl (S)-2-methylbutanoate, the two major components of the thrips aggregation pheromone. These compounds have been offered to O. laevigatus adult females and nymphs of the predatory bugs both in separate and as specific (1:1 or 1:2.3) blends, in experiments involving a dual choice Y-tube olfactometer. None of the compounds attracted adults or nymphs when they were individually supplied. Conversely, they were significantly attracted to both adults and nymphs when offered as a blend. A 1:2.3 (R)-lavandulyl acetate:neryl (S)-2-methylbutanoate blend was attractive to both nymphs and adults, while a 1:1 blend elicited response only in nymphs. These results suggest that specific blends of these compounds from the aggregation pheromone may be used as an attractant to O. laevigatus. The results of this work highlight the importance of studying olfactory responses of natural enemies for a better understanding of their foraging behavior. Potential uses of these results in future studies are discussed.Sun, 01 Oct 2017 00:00:00 GMThttp://hdl.handle.net/10045/743052017-10-01T00:00:00Z